Indexing a trace by insertion of memory snapshots for replay responsiveness

A computer system, comprising:

• one or more hardware processors;
• and
• one or more hardware computer-readable storage media having stored thereon computer-executable instructions that are executable by the one or more processors to cause the computer system to insert memory snapshots during indexing of a trace for responsive trace replay, the computer-executable instructions including instructions that are executable to cause the computer system to perform at least the following:
• identify a plurality of points of interest in execution of one or more executable entities whose execution is traced in one or more first data streams;
• based on the one or more first data streams, replay a traced section of execution of the one or more executable entities preceding each point of interest;
• during replay of each traced section of execution, track which memory addresses are accessed by the one or more executable entities during replay of the section, and at least a most recent value encountered at each memory address during replay of the section;
• and
• record one or more second data streams, including recording a plurality of memory snapshots in connection with the plurality of points of interest into the one or more second data streams, each memory snapshot summarizing memory addresses and values encountered in at least one section of execution preceding each point of interest, wherein the plurality of memory snapshots include one or more of:
• at least one of:
• one or more fixed memory range snapshots, or one or more variable memory range snapshots, and wherein a determination of whether to create a fixed memory range snapshot or a variable memory range snapshot is based on one or more of:
• an amount of memory access locality by the one or more executable entities, or a memory lookup complexity;
• or
• at least one of:
• one or more full memory range snapshots or one or more differential memory range snapshots, and wherein a determination of whether to create a full memory range snapshot or a differential memory range snapshot is based on one or more of:
• a number of memory addresses in a memory range that have been accessed by a section, a disk page size, or a number of levels of snapshot traversal.

A computer program product comprising one or more hardware storage devices having stored thereon computer-executable instructions that are executable by one or more processors of a computer system to cause the computer system to insert memory snapshots during indexing of a trace for responsive trace replay, the computer-executable instructions including instructions that are executable to cause the computer system to perform at least the following:

• identify a plurality of points of interest in execution of one or more executable entities whose execution is traced in one or more first data streams;
• based on the one or more first data streams, replay a traced section of execution of the one or more executable entities preceding each point of interest;
• during replay of each traced section of execution, track which memory addresses are accessed by the one or more executable entities during replay of the section, and at least a most recent value encountered at each memory address during replay of the section;
• and
• record one or more second data streams, including recording a plurality of memory snapshots in connection with the plurality of points of interest into the one or more second data streams, each memory snapshot summarizing memory addresses and values encountered in at least one section of execution preceding each point of interest, wherein the plurality of memory snapshots include at least one of:
• one or more full memory range snapshots or one or more differential memory range snapshots, and wherein a determination of whether to create a full memory range snapshot or a differential memory range snapshot is based on one or more of:
• a number of memory addresses in a memory range that have been accessed by a section, a disk page size, or a number of levels of snapshot traversal.